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PixArt Imaging Inc.

PAC7640 Product Datasheet

Enhanced QE Global Shutter Image Sensor

Version 1.1 | 11 Sep 2015 | 41002EN

PixArt Imaging Inc. http://www.pixart.com

All rights reserved. Any portion in this paper shall not be reproduced, copied, or transformed to any other forms without permission.

5.0 Power States

Table 11. Operational States

States

Functional Description

OFF

No power supply, all the voltage rails and clocks are gated.

RESET

This mode is entered when power-up sequence is executed and RESETB is held low. The

sensor stays in this state as long as RESETB is held low. High on RESETB will transition the

sensor to Ready mode. After power up, when the sensor is waiting for RESETB to go high, all

the rails to the individual functional blocks shall be internally gated. Any time the RESETB is

pulled low the sensor shall enter this mode.

The sensor is transitioned to this mode when RESETB is set to high. This mode can be thought

of as a mode for re-initialization of the registers if they are different from the default register

settings. All the rails and clocks are enabled. There is no capture or transmission of data on

the MIPI lanes. All the functional blocks are enabled. Transition to Sleep can be triggered

when a pre-programmed timer expires.

The sensor will enter this mode when streaming is enabled by setting R_MODE_SELECT = 1 in

the ready state. The sensor will capture image and the data is transmitted on the MIPI lanes

based on the settings for readout. Frame rate can be changed to any frame rate within design

limitation. All the power rails and clocks are enabled as required. R_MODE_SELECT = 0

transitions the sensor back to the Ready mode. Various configurations for Stream mode like

readout and synchronization settings. See more details from operation examples.

(Frame ON Demand)

In FOD the capture and transmission happens in response to an I/O that is controlled by the

host. Transition to this state from a ready state happens when R_MODE_SELECT = 3. The

FOD_TRI is configures as input before the transition. This is very similar to stream state and

the only delta is in the number of frames being transmitted. In the stream state the frames

are continuously transmitted based on a certain frame rate. In FOD mode even though the

capture happens at the same frame rates only a few frames are captured and transmitted.

The number of frames, N(up to 100), to be transmitted is programmable. While the sensor is

in this mode it is waiting for a rising edge, minimum 1us hold time, on the FOD_TRI pin to

begin the capture and transmission of N frames. The sensor shall transition back to ready

state when R_MODE_SELECT = 0.

the user will transition anytime by setting R_SW_PowerDown_EnH = 1. In autonomous

transition happens when the timer, R_Sleep_Timer, expires. The sensor stays in this mode

until the user transitions back to Ready mode by setting R_SW_PowerDown_EnH = 0. The

MIPI and image capture are disabled. All the register settings initialized during the Ready

mode are retained.

Notes:

1.

Transition relative registers: Bank0: 0x09, 0x10, 0x14, 0x15, 0x16, 0x6D.

2.

Synchronization relative registers: Bank0: 0x0B, 0x11

3.

Readout relative registers: Bank1: 0x28, 0x29, 0x2A